Eobeet patteeson and button patteeson



B. 8:. S. PATTERSDN.

Grinding-Mills.

' Patented Ot. 14,1873.`

UNITED STATES 'PATENT FFICE.

ROBERT PATTERSON AND SUTTON PATTERSON, OF NEWOASTLE-UPON-TYNE,

ENGLAND. l

lanenovlawuzrcr-uv G RlNnlvNe-MILLS.

Specification forming part of Letters Patent No. 143,710, dated October 14, 1873 5 application tiled l July 14, 1873.

To all whom t may concern.-

Be it known that we, ROBERT PATTERsoN and SUTTON PATTERSON, both of the borough and county of Newcastle-upon-Tyne, England, millstone manufacturers, have invented certain Improvements in Adjustable Millstones, of which the following is a specification:

This invention relates to improvements in the formation of millstones and the means of adjusting the grindingsurfaces, being more particularly applicable to millstones for grinding coprolites or cement, where the surfaces of the stones are rapidly worn away and where the labor of adjusting them is necessarily very great. The invention consists in providing the upper stone with anadjustable inner lining, to

we will proceed to describe the drawing hereto` attached, in which- Figure 1 represents a central vertical section through both millstones; Fig. 2, a top view of the upper millstone; and Fig. 3, a detail central section of the casing or lining of the upper millstone.

Similar letters of reference indicate corresponding parts in all the igures.

The lower stone G is formed with a circular recess, G', for the insertion of a number of rings, D, which rest upon a set-off, D1, reducing the orifice Gr' through the stone. The rings D are for the purpose of adjusting the central bush D2, the whole being secured by screw-bolts E, connecting the bush D2 and the metal ring A below the oriiice G', and bearing against the under surface of the lower ystone Gr. The driver'` and suspender S of the upper stone GX are likewise rendered adjustable by means of pack ing-pieces O inserted into slots in the recessed .projecting ribs T1v formed in the circular casing or lining T arranged to move vertically in grooves formed inthe eye or orijice of the upper stone GX. The cylindrical lining Tl is the space between the bolt and the bottom of' the slot T.

When the grinding-surface ofthe upper stone is worn away, the nuts of the bolts T3 are loosened and the lining T is raised a suitable dis-- tance within the eye or oriiice of the stone. Shorter filling-pieces O are then inserted in the slots below the bolts T, which are then screwed up tightly again to secure the lining T within the orifice of the upper stone Gr".

When the grinding-surfaces of millstones (formed and mounted as previously described) Wear away, they can be readily adjusted to any extent by taking out one or more of the rings D in the eye of the lower stone, or one or more of the packing-pieces O let into the slots T1 cut in the lining T of the upper stone, or by substituting other iilling-pieces, C and D, of different lengths and thicknesses.

The screw-threads upon the bolts E are of suitable extent to admit of any reduction in the thickness of the stones, as will be readily understood on examining the drawings.

Having thus described the nature of our invention, and the manner of carrying the same into practice, we would have it understood that we do not conne ourselves to the exact details hereinbefore described and shown in the drawings; but

What we claim is- The driver S combined with the adjustable lining T of the stone Gr", when, said lining is `slotted and secured substantially as speciiied.

ROBT. PATTERSON. SUTTON PATTERSON. Witnesses:

W. WILSON, Mason,

Newcastle-oa-Tg/ac. THOS. CROSBIE, Mason,

NewcastZe-oa-Tyne. 

